Chilling new details have emerged revealing the shocking scale of the Fukushima nuclear disaster and the incredible bravery of the technicians, firemen and soldiers who risked their lives to avert a total meltdown.

For his new documentary - Inside Japan’s Nuclear Meltdown - American reporter Dan Edge talked to many of the workers who stayed behind at the stricken plant after the tsunami hit and find how the crisis unfolded.

While the outside world was being briefed on the dangers of radiation being released into the atmosphere, the technicians were battling to prevent something far more serious - a reactor exploding and scattering nuclear fuel over the surrounding area.

Terror in the darkness: A still from the documentary Inside Japan's Nuclear Meltdown shows Fukushima technicians fumbling in the darkness as they struggle to find out exactly what was happening in the crippled reactor